BoostedEBZ06

Okay fellas so I just picked up my 08 Z it has a new engine with 10k miles and I had the dealer do the wiggle test all are within spec but I'm not taking any chances!

So I'm going to be sending the heads to WCCH for a stage 1 job I don't think the porting is worth the extra 1K for 10-15hp. I will also be doing a cam.

My question is which exhaust valves should I use?

Katech says the stock valves aren't the problem which logic tells me I should agree that the guides are the issue here. Although I've seen some talk about the sodium making the guides wear prematurely but the LS6 has sodium filled valves correct?

Why is everyone doing the SS valves?

What about a hollow stem valve?

I just don't wait to add a ton of weight to the valvetrain and have float issue I still want to turn 7K RPM with no issues.

'06 Quicksilver Z06

Plenty of people in here run solid stemmed SS valves with no trouble turning 7K RPM.

The myth that SS valves would limit the 7K redline, has long since been put to rest, by several in here, myself included.

If solid SS valves limited the 7K redline in these cars, well then Mast, PRC, Advanced Induction, Darin Morgan, AFR and a long list of other companies that build LS7 cylinder heads with solid SS valves, wouldn't be using them.

See what the people at the shop where you are sending your heads have to say about their experiences, and go from that.

Good luck

LFZ

Really ? Your guides are in spec and you don't want to take any chances? This forum got you that spooked??? LOL!

BoostedEBZ06

Sounds good ill probably just go with the SS valves.

I found a post from someone at WCCH saying that the stock sodium valve is transferring heat which in turn cooks the oil and does not lubricate which makes the guide wear.

BoostedEBZ06

Ummm yes! Haha I can afford $1,500 for heads not $15,000 for a new engine. Yes they are all in spec at this time but I don't really see it lasting especially after a cam swap.

Mark2009

1. As the other poster noted, that the addition of weight to a valvetrain has any importance at all is indeed a myth... just ask any valvetrain engineer

2. WCCH does not seem to have an account here, so it is unlikely that you have seen anything they have posted here. That does not mean you will not read things that they have supposedly said; unfortunately it means that you'll have to take someone's word that they actually said it. That applies to much of the second hand info you will read here, claiming that so-and-so said such-and-such. Sometimes it actually was said, sometimes not, sometimes it is misinterpreted or taken out of context. Generally speaking, the chaffe tends to bury the wheat. However, the oil cooking theory is probably as valid as the various other reasonable theories, which means it may have about a 25% chance of being correct.

If it were me and I were afraid of the sodium valve I would look real hard at the new Ferrea semi-hollow exhaust valve... with a lighter aftermarket valve spring and titanium retainer the net valvetrain weight will be pretty much the same as stock, which should be the ultimate goal if at all possible. You might run that idea by WCCH and see what they have to say about it.

BoostedEBZ06

Thanks for the heads up ill look into those valves when I call WCCH.

Sorry for the mis information it wasn't a post it was an email from Richard @WCCH that someone posted in a thread on LS1tech.

It can be seen here.

http://m.ls1tech.com/forums/showthread.php?t=1291552

LS9Drew

What cam u getting?

BoostedEBZ06

I'm gonna get Ricks smog cam most likely.

Jawnathin

Good choice!

Dirty Howie

Well, the simple answer to your question is that you should use the SS valves and the reason why is that Richard recommends them. His track record with his setup is exceptional. I followed his advise

Oh, and I wind mine out to 7K rpm every time I hit the track.


DH

'06 Quicksilver Z06

A couple of other things I noticed in your postings above are significant.

To the top post, I keep track of the LS7 failures on this forum.

Of all the modified failures I looked at, I found a significant number of exhaust valve failures in "cam only" setups on this forum.

Cam only, would of course indicate that the stock valves were being used in the setup.

You can take this information and do what you decide to do with it.

Where you see a name listed more than one time, that person had more than one engine failure.

http://forums.corvetteforum.com/1581584713-post108.html

This was a listing I kept of both stock and modified LS7 engine failures up until around September of 2012, after the number of cars got too big, and after the point to where I had seen enough to know that something was definitely not right.

I emphasize that these failures fall into all categories, and not just valve failures.

The stock failures documented to that point, are indicated in the top of the list, and the modified failures at the bottom.

Not all of the modified failures are hyperlinked, because there simply became too many of them to do for any one man, and like I say, I had seen enough to convince me that there was a significant problem.

I believe that there are somewhere around 150 cars on those two listings. Where the names are not hyperlinked, you are free to do a search of their posts so that you can read their own reports.

http://forums.corvetteforum.com/1581585975-post128.html

About a year later, I started keeping track of those members who had gone to a non stock and "heavier" exhaust valve, in a listing that is known as "The Registry".

In that listing, also at the bottom, I started keeping a list of failures reported from around June of 2012 up until present.

I used an asterik in cases where the failure had just missed the June 2012 startup period by a few days. Some had actually occurred and had been documented while I had been running the first list, but had been overlooked during the time I was keeping the first list.

These are included in "The Registry". Approximately 30 failed cars are on it.

This adds onto that approximately 150 LS7 engine failures which had already been located on this forum prior to the inception of "The Registry".

http://forums.corvetteforum.com/1581929353-post1.html

As you can see, from this latest listing, that from around June of 2012, up until now, we are pushing, or better put, I have found descriptions of, somewhere around 30 additional LS7 engine failures on this forum over that 16 month period. Or about 2 new LS7 engine failures described in here per month, going back about 16 months.

Small wonder that they really aren't news anymore.

At least three more cars are to be added to the listing at the bottom of "The Registry" which I have not gotten around to adding yet.

http://forums.corvetteforum.com/c6-z...post1583791561

http://forums.corvetteforum.com/c6-z...-the-dust.html

http://forums.corvetteforum.com/c6-z...e-failure.html

I try to add the cars in pairs in order to save myself some work listing them, and in order to not get backed up on the listing. But after awhile it becomes overwhelming, as you can see that I have a "backlog" of three cars I need to add in order to keep the listing current.

The most important thing to take from all that I am telling you above, is that however many cars you see on those listings which have failed up until this point, you would see even MORE were it not for the discussions on this matter, and the efforts taken by those who elected to do something about the LS7 valve train issue. And whatever good which has come of this matter, occurred due to the diligence, tenacity and perseverance of the members right in here, and NOT General Motors.

They haven't lifted a finger, except the middle one to point at us.

At any rate, I would definitely agree that if you are going to go with a cam, then SS valves are the way that I would go.

Finally, as you say that you are going to have the heads done, I hope that you can let us know, how the actual guide measurements of your existing heads, correlate with what your dealership found on it's wiggle test.

This piece of information would be very valuable.

Thanks and good luck.

Mark Wade

Not sure if this will interest you we have a class of race cars in New zealand called Super tourers tarseal track cars, they have holden and ford bodies but they all run Ls7 engines with very limited modifications they also use the stock heads with stock ex valves ,these cars hit the rev limiter all day long in other words they they get well and truely thrashed and to my knowledge have not had any valve failures .Del west valves are used in lots of very high performance race engines so why arnt they good enough for corvettes, good luck.

ClarksZ06

I agree 100%. This is the route I would of taken if the ferrea light weight hollow valves would of been available when I had my heads done. Through all the research and reading I believe this is the best upgrade or compromise out there for a much more reliable valve while keeping the valve train as light and stable as possible.
My next build will be with these valves, Katech's .660 lift springs and retainers, and their K501 cam. I really want that 7,300 rpm redline !
It doesn't get much cooler than a cam that is still making power above 6,500 rpm in a 427 with good drivability too

But like Ricky says the track record with the SS valves is proven and working well as long as the guides and valve job are done at the same time. I have confidence in my motor since WCCH worked my stockers over.
To the OP, Either valve will improve your durability. Enjoy !

ramairws6

Very dangerous question in this place....

0PalmerPerformance

As long as your exhaust valve is still lighter than your intake valve, the exhaust valve will never be the valvetrain limitation.

ramairws6

Sorry, but i don't believe the exhaust valves are Del West. The intakes are but not the exhaust valves

ramairws6

Wow, someone with some logic for once. Who would have thunk it

Mark2009

There are a few here, but they tend to get shouted down

Now tell the nice man the weights of the various valves that have been mentioned here

nitrojunky

are the ramp rates / lift / accelerations similar for the exhaust valve?